Chevy & GMC Vans

Hello folks,

seems like I have a gremlin in my car, literally

Changed my stock fuel pump for an ebay cheapy back in February 2008. Van has been stationary for about 10 months, but is regularly run every wk. That pump seemed to stop responding, I.e. it didn't prime up when turning the key.. though sometimes it did.

So, I changed it last month for a AC Delco item with a new Fram fuel filter. Ran fine straight away and has done since I installed it just like the cheapy ebay one although not as noisy.

Today, I was working on the van and as usual started the van up.. This time it didn't prime up and instantly I got the chills thinking it can't be the pump gone again!? i've done 0 miles!!

So.. Got me thinking, could I have another problem else where I should be looking at? Possibly the relays? I swapped over the ones under the engine bay (a/c pump with the fuel pump relay) and didn't make a difference, although I'm not sure if either relay works since the AC has been removed from the car.

Could it be Ignition module?
EGR valve?
Injector?

What stops the fuel pump from priming up?

For all I know the pumps ive changed could have been fine and the other gremlin is still at large but i've simply not spotted it

Any ideas would be great, its starting to give me sleepless nights #-o

Thanks,
Am

What's the fuel pressure look like?

Sounds like the pump isn't even coming on - is that correct? If it is and it still won't start, you need to check for fuel pressure. If the pump simply isn't running, look for the grey colored wire with a connector that is located right on the wire harness right above the heater and a/c box on the right side of the engine compartment. You can jump that straight to battery positive and the pump will run. Test that and let us know.

If it's a 6 injector CPFI it could be in the crab assembly. Very hard to test. I would check the wire harness near the fuel pump - tank.

ihatemybike wrote:What's the fuel pressure look like?

not sure, i dont have a fuel pressure gauge.. i believe there is a valve somewhere under the hood to install one in without having to break the line?

LiftedAWDAstro wrote:Sounds like the pump isn't even coming on - is that correct? If it is and it still won't start, you need to check for fuel pressure. If the pump simply isn't running, look for the grey colored wire with a connector that is located right on the wire harness right above the heater and a/c box on the right side of the engine compartment. You can jump that straight to battery positive and the pump will run. Test that and let us know.

Thats right, the pump isn't coming on and priming up (2 seconds)
I'll try that and report back later today.

mikedamech wrote:If it's a 6 injector CPFI it could be in the crab assembly. Very hard to test. I would check the wire harness near the fuel pump - tank.

OK, i'll check the harness/plug at the tank.

--
Thanks guys

mikedamech wrote:If it's a 6 injector CPFI it could be in the crab assembly. Very hard to test. I would check the wire harness near the fuel pump - tank.

Well looks like you were right.

Checked the harness at the pump, then round cylinderical shaped one. Disconnected, reconnected. Turned the ignition, pump primed

So, I checked all the pins, wires going into the harness and found no fault. Did continuity check, no problems.

Sprayed a load of WD-40 on the contact pins and over the harness where the wires go in.. just in case there was any oxidation.. And i'll see how it goes for the next few days.

I'm hoping that that is all it is